Energy balance and body weight regulation
As many of you know, I am in university part-time obtaining a Bachelor of Science in Kinesiology. And while I mainly teach Pilates, I have been a certified personal trainer since 1999. And I love to write about what I am currently researching concerning health and fitness. Presently, I am enrolled in a 300-level nutrition course, and I have to say it’s not been my favourite course thus far. It’s covering many of the topics I have already learned from my Precision Nutrition Level 1 coaching program. But it’s still fun to review!
This week the topic is energy balance and body weight regulation. We have all heard about calories in and calories out, right? But of course it’s not that simple. We know that sociodemographic factors and our social networks influence our weight, as well as, depression and anxiety. We also know that how much physical activity we do every day is important, and not just “exercise” but our daily movements. Physical activity is any bodily movement that results in energy expenditure verses exercise that is planned, structured, and repetitive with the purpose to build strength and endurance. We need both.
And then there is genetics. We have discovered that the hormone leptin helps with feelings of satiety, and new research may be pointing to those with obesity to have trouble receiving those leptin receptors. A few months back, I did a 30 minute presentation for a university course on the new “diet” drug called Ozempic. Ozempic helps the same way, the semaglutide mimics your naturally occurring GLP-1 hormone which sends signals to your brain that you are full. Bariatric surgery does that same thing.
Weight management. Such an individualized journey. What I love about the National Weight Control Registry is that it’s a large, prospective study of individuals who have lost a significant amount of weight (over 30lbs) and have successfully kept it off. I have written about this registry in more detail before. Almost 89% of successful weight loss participants reported that both diet and physical activity were part of their weight loss plan. Here is where those helpful global physical activity guidelines I write about so often come into play:
150 minutes of moderate physical activity weekly
2 or more strength based workouts weekly (Pilates counts!)
In the registry, only 10% report using diet alone, and only 1% used only exercise. On average, the registry participants engage in 60-90 minutes of physical activity daily (walking, gardening, dancing, Pilates, strength training, aerobics, running, etc). They also eat breakfast every morning and monitor their weight frequently.
If you are curious about an estimate of how many calories you individually need to consume, here is a guide I wrote a few years back:
Step by step guide:
Step 1: weight (lbs) x 10 = basal metabolic rate (BMR)
Step 2: BMR x activity factor = total energy expenditure (TEE) . Daily activity factor: very light 1.2 (desk job, not exercising), low active 1.5 (desk job, light exercise), active 1.7 (desk job, exercises most days of the week), heavy 1.9-2.1 (physical labour, athlete, vigorous exercise).
Step 3: If you are hoping to lose weight, only cut out 250 calories per day, or dieting will simply slow down your metabolism. TEE - 250 = weight loss calories.
Step 4: Macros. It’s recommended for people who resistance train 2-3x weekly to ingest 0.8g-1g of protein per 1 pound of ideal body weight. After calculating your protein grams, figure out how much that is in percentage of total calories (4g x total grams = protein calories x 100 = protein %). Then figure out your fat (25%) intake (total calories x 25%/9g). The rest of your calories are carbs: total calories - fat calories and protein calories = carb calories/4g = carb grams.
Example: I weigh 128lbs.
Step 1: 128x10 = 1280 calories is my BMR.
Step 2: 1280x1.7 = 2176 calories. This number is quite accurate to what I have found to maintain my current weight.
Step 3: If I wanted to lose weight 2176 - 250 = 1926 daily calories for weight loss with my current activity level. But I want to maintain current weight, so I don’t minus 250.
Step 4: To calculate my recommended protein: 0.8g x 128 = 102g or 1g x 128 = 128g. 128g x 4g = 512 protein calories. For fat, I aim to consume roughly 25%: 2176 (total calories) x 0.25 = 544 calories from fat. 544 calories/ 9 grams = 60g of fat. Lastly the rest for my intake is from carbs. If 128g x 4c = 512 calories of protein and 544 calories from fat, that means 1056 calories is for carbs/ 4g = 264g of carbs.
So my daily macros are:
264g carbs (roughly 50%)
128g protein (25%)
57g fat (roughly 25%)
I don’t track my macros all the time, just once and awhile to stay on target with my health and fitness goals.
Resources:
McGuire, M., & Beerman, K. A. (2017). NUTR2 (Student edition). Cengage Learning.
Dhillon, S. (2018). Semaglutide: First global approval. Drugs, 78(2), 275–284. https://doi.org/10.1007/s40265-018-0871-0
National Weight Control Registry: http://www.nwcr.ws/
